TY - JOUR
T1 - A 100-year record of changes in water renewal rate in Sermilik Fjord and its influence on calving of Helheim Glacier, Southeast Greenland
AU - Andresen, Camilla S.
AU - Schmidt, Sabine
AU - Seidenkrantz, Marit-Solveig
AU - Straneo, Fiammetta
AU - Grycel, Aleksandra
AU - Hass, Christian H.
AU - Kjær, Kurt Henrik
AU - Nørgaard-Pedersen, Niels
AU - Dyke, Laurence M.
AU - Olsen, Jesper
AU - Kuijpers, Antoon
PY - 2014/8/15
Y1 - 2014/8/15
N2 - Here we present a 100 year long proxy record for the renewal rate of the subsurface ocean waters in Sermilik Fjord at the edge of Helheim Glacier, based on investigations of two sediment cores (ER11-24 and ER11-25) obtained from the head of the fjord. By calculating the mean sortable silt (SS-) in current-sorted melt water plume sediments we find that episodes of increased water renewal rates lasting 3-5 years coincide with a positive North Atlantic Oscillation (NAO) index. This is not surprising as low pressure systems and northeasterly storms are observed more frequently along the east coast of Greenland during positive NAO years as a result of the northward shift in the North Atlantic storm track. Previous studies of sediment cores obtained from the mid-region of the fjord showed that Helheim Glacier destabilization coincides with a negative NAO index. Therefore we conclude that inter-annual variability in storm-induced flushing of Sermilik Fjord and thus the water renewal rate towards the glacier margin is not the controlling factor for inter-annual variability in Helheim Glacier destabilization. Such knowledge may have implications on predictive model studies of ice-ocean interactions and glacier behavior.
AB - Here we present a 100 year long proxy record for the renewal rate of the subsurface ocean waters in Sermilik Fjord at the edge of Helheim Glacier, based on investigations of two sediment cores (ER11-24 and ER11-25) obtained from the head of the fjord. By calculating the mean sortable silt (SS-) in current-sorted melt water plume sediments we find that episodes of increased water renewal rates lasting 3-5 years coincide with a positive North Atlantic Oscillation (NAO) index. This is not surprising as low pressure systems and northeasterly storms are observed more frequently along the east coast of Greenland during positive NAO years as a result of the northward shift in the North Atlantic storm track. Previous studies of sediment cores obtained from the mid-region of the fjord showed that Helheim Glacier destabilization coincides with a negative NAO index. Therefore we conclude that inter-annual variability in storm-induced flushing of Sermilik Fjord and thus the water renewal rate towards the glacier margin is not the controlling factor for inter-annual variability in Helheim Glacier destabilization. Such knowledge may have implications on predictive model studies of ice-ocean interactions and glacier behavior.
KW - Fjord circulation
KW - Glacial plume sedimentation
KW - Ice-ocean interactions
KW - North Atlantic oscillation
KW - Outlet glaciers
KW - SE Greenland
UR - http://www.scopus.com/inward/record.url?scp=84903702308&partnerID=8YFLogxK
U2 - 10.1016/j.csr.2014.05.017
DO - 10.1016/j.csr.2014.05.017
M3 - Article
SN - 0278-4343
VL - 85
SP - 21
EP - 29
JO - Continental Shelf Research
JF - Continental Shelf Research
ER -